1. Field of the Invention
The present invention relates to methods for making liquid ejection heads which are used for head cartridges for generating liquid droplets by an ink jet (liquid ejection) system or the like, liquid ejection apparatuses, etc.
The present invention also relates to methods for making liquid ejection heads which can be used for apparatuses, such as printers, copying machines, facsimile machines provided with communication systems, and word processors provided with printers, in which recording is performed on recording media, such as paper, yarn, fibers, textiles, leather, metal, plastic, glass, and ceramic, and also for recording apparatuses compositely combined with various processors for industrial use. In this specification, the term “recording” means not only providing an image having meaning, such as characters or graphics, on a recording medium, but also providing an image having no meaning, such as patterns, on a recording medium.
2. Description of the Related Art
Generally, in an on-demand type liquid ejection recording head, pressure chambers are formed by placing a nozzle plate having a plurality of nozzles so as to face a diaphragm which can be partially elastically deformed by piezoelectric elements (piezoelectric vibrators). A liquid, such as ink, is introduced by suction into the pressure chambers due to contraction and elongation of the piezoelectric elements, and then liquid droplets are ejected from the nozzles due to elongation of the piezoelectric elements. In order to improve the connection between the piezoelectric elements and the diaphragm, for example, as disclosed in U.S. Pat. No. 4,418,355, a coupling member is interposed between each piezoelectric element and the diaphragm so that the displacement of the piezoelectric element is efficiently transmitted to the pressure chamber. Japanese Patent Publication No. 63-25942 also discloses an ejection apparatus using a foot to improve the connection. In either case, the piezoelectric elements and the members constituting the pressure chambers are separately formed and then joined to each other. In the joining process, high alignment accuracy is required, resulting in an increase in manufacturing cost. It is also likely that the displacement of the piezoelectric elements is not efficiently transmitted to the pressure chambers or the displacement of the piezoelectric elements is transmitted to portions which should not have been displaced, resulting in instability of the meniscuses in the nozzles, i.e., cross-talk.